pgas.src

#include "zeus2d.def"
c=======================================================================
c////////////////////////  SUBROUTINE PGAS  \\\\\\\\\\\\\\\\\\\\\\\\\\\\
c
      subroutine pgas
c
c  PURPOSE: Calculates the gas pressure at each zone centered point on
c  the grid.  If gamma < 0, then the pressure is set to 0 (allows for
c  pressure free evolution calculations).  The pressure is computed in
c  ghost zones for diagnostics, though it is never needed there.
c  If gamma=1, an isothermal EOS is used, ie p=ciso**2*d
c
c  EXTERNALS: [none]
c
c  LOCALS:
c-----------------------------------------------------------------------
      implicit NONE
#include "param.h"
#include "grid.h"
#include "field.h"
#include "root.h"
      integer  i,j
c\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\///////////////////////////////////
c=======================================================================
c
      if ((gamma-1.0) .gt. 0.0) then
      do 20 j=js-2,je+2
        do 10 i=iim2(j),iop2(j)
          p(i,j) = (gamma - 1.0)*e(i,j)
10      continue
20    continue
      elseif ((gamma-1.0) .eq. 0.0) then
      do 40 j=js-2,je+2
        do 30 i=iim2(j),iop2(j)
          p(i,j) = ciso**2*d(i,j)
30      continue
40    continue
      else
      do 60 j=js-2,je+2
        do 50 i=iim2(j),iop2(j)
          p(i,j) = 0.0
50      continue
60    continue
      endif
c
      return
      end